
Penny has no interest
in subatomic PARTICLE research.
The Big Bang Theory Season 3, Episode 15

Here, we have a highly gifted researcher
in the field of PARTICLE physics...
The Big Bang Theory Season 3, Episode 15

A sigma PARTICLE.
The Big Bang Theory Season 1, Episode 13

...of a subatomic PARTICLE
called the Higgs boson.
The Big Bang Theory Season 6, Episode 3

inventing a new
dark matter PARTICLE
The Big Bang Theory Season 11, Episode 13